The present invention relates to a bicycle front fork packing devices adapted to secure the top coupling tube of the front fork of a bicycle to the head tube thereof, and relates more particularly to such a bicycle front fork packing device which seals out rain water when installed.
A regular bicycle front fork packing device is generally comprised of a locating socket mounted around the top coupling tube of the front fork and supported on a ball bearing above the head tube of the bicycle frame, the locating socket having an outer thread and a tapered center through hole, and a split holding-down ring fitted into the tapered center through hole of the outer thread of the locating socket to compress the holding-down ring by forcing an inside annular flange thereof into an outside annular groove on the holding-down ring, causing the holding-down ring and the locating socket to securely fix the front fork to the head tube. Because the design of the outer thread of the locating socket and the annular groove of the holding-down ring complicates the manufacturing process of the bicycle front fork packing device, the manufacturing cost of the bicycle front fork packing device is high. Further, this packing device can not effectively seal out rain water.
The present invention provides a bicycle front fork packing structure which is inexpensive to manufacture, and easy to install. According to the preferred embodiment of the present invention, the bicycle front fork packing structure comprises a bearing assembly mounted on and partially fitted into the top end of the head tube around the top coupling tube of the front fork, a bottom split taper ring supported within the top cover of the bearing assembly, a top split taper ring mounted on the bottom split taper ring around the top coupling tube of the front fork and stopped at the bottom end of the vertical tube of the handlebar stem, and a sealing cover covered on the top cover of the bearing assembly around the bottom end of the vertical tube of the handlebar. The bottom split taper ring is moved up with the bearing assembly and the top split taper ring is forced to expand by the bottom split taper ring and to firmly engage with the inside wall of the sealing cover when the vertical tube of the handlebar stem and the top coupling tube of the front fork are fastened tight.